Knowledge of the whereabouts of individual persons is of general interest in many scenarios, as is having a knowledge of the persons with whom an individual person is associating or has associated with.
For example, the parents of a child or teenager have a legitimate interest in tracking the whereabouts of that child, and knowing who the child's friends are and with whom the child is associating.
Similarly, in a school environment teachers or administrators of the school have a legitimate interest in monitoring which pupils or students have turned up for school, and with which groups of persons they are associating with whilst at school. Crime prevention authorities such as the police take a high degree of interest in the contacts, connections and associations of known or suspected criminals, as well as their patterns of movement and favored locations.
There are several known technologies which are currently used to track the whereabouts of persons. In the field of electronic tagging, it is known to fix a transceiver to a person's limb in order to track their whereabouts and physical location. Such systems are known as “electronic tags.” Whilst such systems give authorities some knowledge of a person's whereabouts and physical location, they give no specific insight into the activities or associations of that person. Further, in order to apply an electronic tag to a person, there must be legal authority to do so, and in general, in the UK, once a tag is applied to a person, the person wearing the tag is not at liberty to remove the tag without breaching an order of court. This restricts the use of such electronic tags to a limited class of known criminals, and therefore also limits its usefulness to the crime prevention authorities. Further, there is no possibility that such monitoring is covert because the wearer of the electronic tag is always aware that the tag is attached and is being monitored.
In another scenario, in some countries, visitors to the country need to report to a local police station at regular intervals, for example daily or weekly. There is a problem that this places restrictions on the person's movement within the country, and also places a burden on the local police authorities in being available to acknowledge daily or weekly visits to police stations.
It is known from other fields of monitoring, such as vehicle tracking, to provide wireless enabled digital tracking devices having location sensors, for example global positioning system (GPS) sensors, which are remotely interogable for monitoring the physical location of the vehicle to within the range of approximately plus or minus 10 meters via a satellite link and/or a terrestrial mobile phone network.
More advanced location positioning systems have been developed for military use. However in many cases technical details of these are not publicly available, and therefore these systems do not form part of the state of the art.
However, in general there is no current technology which is broadly applicable to a wide range of persons, and which has high market penetration and wide spread low cost availability which enables a knowledge of a persons activities and associations to be recorded, which are generally are non intrusive on that persons activities.